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Topic: Maytag gas dryer Model NGD7200TW (Read 5576 times)

2007 floor model bought 2.5 years ago. Burner burns for only 10 seconds, shuts off, off about 1.5 minutes then burns 10 seconds. I have replaced coils( even though they tested good) = no change. Removed high limit thermostat from circuit= burner continues to burn. Sure looks like that is the problem, but reading another post whereas another had identical conditions, but replacing the coils cured his problem. So I replaced coils, to no avail. Is this high limit therm. the next likely problem? It has a L230-50F in it. Thanks for help.

I tested the high-limit thermostat yesterday with electric fry pan. Thermostat opened at correct temperature. Re-installed HLT, retested = same results. re-tested thermistor which now reads 2.3K ohms rather than the 10K ohms measured previously and now motor runs, drum turns but igniter never comes on and of course, no gas flow. So is it the thermistor? With that new reading on the thermistor I will wait to test with exhaust pipe removed, unless you think that could still be the problem. Thank you!

Since last post I have tested with exhaust pipe removed= no change. I then exposed the blower wheel and discovered that the vanes were @ half full of lint. After cleaning and putting cover back on, retested. What I have is after the thermistor has sat for awhile the resistance reads about 11k ohms and the igniter lights and the burner burns for @ 10 seconds, then goes out. Immediately testing thermistor shows 2.3K ohms at this point. Is it the thermistor??

In your first post you said burner runs 10 seconds ,shuts off about 1.5 min. than burns for 10 seconds.My Question is do you see the glow coil glow and ignite and shut off and keep doing this fast rapid matter.Meaning comes on with heat goes off awhile and comes back on with heat but never stays on long?but is always igniting.If so you could have a weak flame sensor.Rare but have seen it happen.Part#338906.Thermistor at 77degrees will be around 10Kohms.I have had them check out good with ohm meter and be bad.May want to try a new thermistor.Or both parts good luck.Thermistor # 35001191.

Glow coil comes on, in a few seconds gas ignites and burns for 10-13 seconds on first ignition. Then flame goes out. And glow coil is not on. After @ 60 seconds glow coil comes on followed by gas ignites. Gas burns @ 8 seconds this time and all following times. Dryer continues this cycle of @ 8 seconds burn, flame out, 60 seconds no glow, glow on, gas burn. In a properly functioning system, does the glow coil stay on or go off while the gas is burning?

No glow coil does not stay on after ignites it is shut off by flame seńsor.It sounds to me that you have a bad flame sensor that keeps the glow coil off until thermistor cycle heat off.But you could have a bad thermistor.I guess this rapid cycle is with clothes in dryer to.One way to tell if flame sensor is bad would be to pull a wire off flame sensor after it ignites and with clothes in dryer.The flame should stay on until thermistor cycles which would be a long time with wet clothes in dryer.But you would have to make sure the wire you pull off does not touch anything metal or you.Might want to just change both parts as they don't cost that much.For your own safety .

Today thermistor arrived. Installed. Same results. Retested heat sensor in un-heated state = good continuity. Upon flameout retests as open. Watched with ohm meter and when the approximately 60 seconds of cool-down time passed, the ohmmeter jumps back to short. I believe I have found the culprit and of course wish that I had done this test at the onset. Hopefully next post will be that new flame sensor indeed makes the dryer operate correctly.